Biphenyltetracarboxylic acid dianhydride and process for producing the same, and polyimide formed from the same and process for producing the same
US8299273B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2010 |
| Grant date | Oct 30, 2012 |
| Priority date | — |
| Expiry date | Aug 12, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G73/10
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
To provide a process for producing BPDA whereby high productivity is attained while high purity is maintained.A process for producing biphenyltetracarboxylic acid dianhydride, which comprises heating biphenyltetracarboxylic acid to produce biphenyltetracarboxylic acid dianhydride, characterized in that the heating is carried out at a pressure of from 1×102 Pa to 1.1×105 Pa to a maximum temperature in a range of from 210° C. to 250° C. in such a manner that the temperature rising rate is higher than 50° C./hr for a period of at least ¼ of the time for the temperature rise from 60° C. to 210° C., and the temperature is maintained to be from 150° C. to 250° C. for from 0.5 to 10 hours.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.